Head gimbal assemblies (HGAs) are used in disc drives to read and write data to media discs in the disc drive. A disc drive may include one HGA for every recordable disc surface in the drive. For example, a disc drive utilizing both sides of its media discs may include two HGAs for every media disc in the disc drive.
Each HGA in a disc drive commonly includes a head with read and write transducers. The head is supported by a flexible load beam, which attaches to a base plate of the HGA. The base plate connects to a stable platform during operation of the HGA. A tail extends from the base plate to provide electrical connection paths between the head and either disc drive circuitry or testing circuitry.
In the disc drive industry, HGAs may be individually tested prior to installation in a disc drive. Testing an HGA may include positioning the HGA adjacent to a rotating test disc and reading to and/or writing from the test disc with the HGA. The position of the read head on the HGA must remain stable to allow accurate testing of the HGA to reliably determine its suitability for inclusion in a disc drive. For example, performances of an HGA during read and write operations may be dependent the location and skew of the HGA relative to the test disc.